Steam-valve



NTE STATE@ PATENT GFFQE.

G. RIESEGK, 0F PITTSBURG, PENNSYLVANIA.

STEAM-VALVE.

Specification forming part of Letters Patent No. 21,151, dated August 10, 1858i; Reissued February T0 all whom it may concern:

Be it known that I, GEORGE RIEsEoK, of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Steam-Valves; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming a part of this speciiication, in whichh Figure l, is a. vertical longitudinal section of a steam valve constructed after my invention. Fig. 2, is a face view of the valve. Fig. 3, is a face view of the valve seat. Fig. et, is a. diagram illustrating my invention.

Similar etters of reference in each of the several figures indicate corresponding parts.

The nature of my invention consists, 1st, in the arrangement hereinafter specified, whereby thatportion of the back of the valve which is exposed to the pressure of the live steam can be reduced to an area. equal or nearly so to the area of the steam receiving ports in the face, Without the necessity of reducing the diameter of the valve, and thus the valve balanced or nearly balanced and held in proper position by the steam, owing to the direct pressure of the live steam upon the back of the valve not being greater than the pressure of the live steam in the receiving ports of the valve.

It consi-sts, 2nd, in combination with the above peculiar construction of valve; in making the face of the valve with six ports, three for receiving and three for exhausting; said ports being arranged in such relation to each other, that one receiving port always stands in line with an exhaust port and that only four of the ports shall be in use when the engine is working forward and the extra two remain in reserve, so that the engine may be instantly and completely reversed, on shifting the valve, by the pressure of steam from a full o-pen port.

To enable others, skilled in the art to make and use my invention, I will proceed to describe its construction and operation.

A, represents the valve seat. It is of ordina-ry construction and may be arranged on a stationary or oscillating engine; when arranged on an oscillating engine it is furnished with a trunnion from a, to Z), but when applied to a stationary engine, the trunnion is not necessary.

B, B, are the two receiving ports in the valve seat and C, the centra-l exhaust port.

D, is the valve, it is of circular form and has a reduced hollow stem E, projecting from its back.

F, F', F2, are three receiving ports and G, G', G2, three exhaust ports in the valve D.`

H, is an enlarged central space for the ports G, G, G2, to exhaust in; this space communicating with the central discharge or main escape exhaust passage. The receivingports F, F, and G, G', receive and exhaust steam as usual when the engine is working forward, and when the valve is shifted or turned on its axis in order to reverse the engine, the ports F2, G2, are

brought into action while the ports F, G,

are thrown out of use.

The ports F, F F2, extend up through the valve obliquely and communicate with the interior of the hollow extended supply stem as shown in Fig. l, while the exhaust ports or chambers o nly extend slightly into the face of the valve and terminate radially in a central space H, in the face of the valve, said space communicating with the exit or main central exhaust passage which has communication with the hollow trunnion on the opposite side of the engine cylinder.

The valve thus constructed is arranged upon the seat, and the outer surface of its stem, that portion of its back between the stem and the circumference of the valve and the entire edge, are covered by an auxiliary steam chest or casing I, which is furnished with a stuffing box at cl, and serves effectually for protecting said surfaces of the valve from being acted upon by the live steam. The valve thus incased has a main steam chest J, constructed upon it, the top of said chest being high enough to allow a space to exist between it and the outer end of the stem of the valve for the passage of the steam through the stem to the ports of the valve. By thus covering the greater portion of the back of the valve and having the .outer end of the stem and the stuiiing box and only a portion of the back of the valve which is equal to the bore of the stem, exposed to the steam the valve will be balanced or nearly balanced between the direct inward pressure of the live steam in the chest and the outward pressure of the live steam in the receiving ports F, F, F2, as the area of said ports is about equal to the area of the surface presented by the stufiing boX, stem and eX- posed part of the back of the valve. This arrangement also avoids the necessity of using a set screw to keep the valve in proper position as the steam will perform the same functions of a set screw at the end of the stem without the disadvantage, as when a set screw is used, of having the valve bind or leak byreason of unequal contraction and expansion of the metal forming the steam chest valve.

K, is the lever for reversing the valve.

The accomplishment of the perfect balancing of the valve in the manner herein specified, inl connection with an instantaneous and perfect reversing of an engine by means of the pressure of a full port of steam, whether the engine is to work back or forward, are very important desiderata in the art of engine building, and have long occupied the minds of the most skilful engine builders.

l/Vhat I claim as my invention and desire to secure by Letters Patent, is-

1. The valve D, with a projecting hollow stem E, which is reduced so that its end pre sents an area only equal, or nearly so to the ports F, F, F2, G, G, G2; in combination with a main steam chest or chamber J, and an auxiliary steam chest or casing I, furnished with a stuffing box CZ, and constructed so as to cover the whole of the back of the valve excepting the end of the stem, or a portion of the back equal or nearly equal to the ports in its face, substantially as and :tor the purposes set forth.

2. In combination with the above, the peculiar manner herein specified of making the face ofthe valve D, with siX ports F, F', F2, G, G', G2, three for receiving and three for exhausting, said ports being arranged in such relation to each other, that when the valve is applied to an oscillating engine, one

receiving port always stands in line with an exhaust port, and that only four of the ports shall be in use when the engine is working forward, and the eXtra two thus kept in reserve,-so that the engine may be reversed, on shifting the valve, by the pressure of f steam Jfrom a full open port, as set forth.

GEORGE RIF. SECK.

Vitnesses 1 G. YORKE AT LEE, W. Ar LEE.

[FIRST PRINTED 1911.] 

